Signaling system



March 5, 1935 E. P. GOODRICH 15 I I SIGNALING SYSTEM File'd oet. 12,1928 s Sheets-Sheet 1 m J I 1 .9' M cu orF 7 INVENTOR ERNEST P. eooomcuBY HIS ATTORNEYS Patented Mar. 5, 1935 UNITED STATES PATENT OFFICESIGNALING SYSTEM Ernest P. Goodrich, Brooklyn, N. Y.

Application October 12, 1928, Serial No. 312,171 17 Claims. (Cl.177-337) This invention relates to signaling systems and in particularit is concerned with signaling systems used for traific control.

The present application is a continuation in part of my applicationSerial No. 117,560 filed June 21st, 1926.'

One object of this invention is to provide an electrically controlledsystem capable of giving signals at one or more stations and subject tocontrol from a central station. It is also an object to provide anautomatically operating system for giving signals at a number ofstations, the system being capable of having each station removed fromthe central control and subjected to local manual control and capablealso of.

adaptation by control from the central station to suit difieringconditions in the area aiiected by the signals. A further object is toprovide a system which will require a minimum of wires and will avoidaltogether the use of power circuits other than one main circuit throughthe signal stations.

It is also an object to adapt such a system to thecontrol of traffic andto make provision therein for variation in the operation to suit thevarying conditions of traffic during the day and night.

Finally it is an object to simplify and to render more flexible thecontrol of signaling systems and to improve the construction of certainof the operating parts of such systems.

The invention is described hereinafter as embodied in a preferred typeof trafiic control system and is so illustrated in the accompanyingdrawings.

In the drawings-- Figure 1 is a diagram of the main A. C. power line fora unified traflic control system and of a complete signal lightoperating unit for any one street intersection.

Figure 2 is a diagram of the main power circuit showing a similar systemadapted for operation by direct current.

Figure 3 shows a reversing switch to maintain uni-directional currentthrough a direct current motor for use when the system is operated ondirect current.

Figure 4 is a view, partly in vertical section, showing a constructionof distributor.

Figure 5 is a view showing a construction of the main control switch.

Figure 6 shows a modification of a part of the system to give adiiTerent type of signaling from that given by the modification ofFigure 1.

Figures '7, 8, 9 and 10 are schematic representations of the successivepositions of the unit switches of the alternator shown in Figure 6,during one cycle of signal combinations.

Figure 11 shows another modification of the alternator to give adifierent type of signaling. Figures 12, 13, 14 and 15 arerepresentations of the successive positions of the unit switches of thealternator of Figure 11 during one cycle.

Figure 16 shows another alternator giving still another type ofsignaling and Figures 1'7, 18, 19

and 20 represent a cycle of its alternator switch positions.

Figure 21 shows a modified main control switch, an alternative of thatshown in Figures 1 and 5, and the manner of connecting it in the system.

Figure 22 represents the selective positions of the two groups of switchunits forming one controller which is a part of the main switch shown inFigure 21-.

The thought which underlies this invention is the provision of a singlemain circuit through all the signal stations, the selectiveestablishment at each station, by mechanism controlled from a centralstation, of feeder circuits for operating the signaling devices to givedifferent types of signaling, and the governing of the respective signalcircuits by a motor driven distributor and other control switches ateach station, these gov- ,erning devices being operated from the mainsupply line and controlled by variation of electrical conditionstherein. The governing of the respective signal circuits thusselectively established includes the determining of the frequency andthe relative duration of the signals given.

The motor driven distributing switch and similar switches at eachstation are themselves subject to energization and control from thecentral station through the main circuit and in like manner the switchfor selectively establishing the signal circuits is controlled from thecentral station. The controlling switch at each station for selecting asbetween the motor controlled distributor and the other devices whosefunction is to govern the signal circuits, and also the switch whichselectively establishes the signal circuits are synchronized so that foreach type of signal circuit established, there will also be establishedthe proper circuits from the main power line through the motor drivendistributor and its associated devices to govern that particular signalcircuit in the desired manner. Although the several signaling stationsare on the same supply line and are thereby subject to simultaneouscontrol from a central station, yet provision is made for individualcontrol of any one signaling station at that station when desired.

By such a system, uniformity and synchronization of operation of signalsat a number of stations are obtained, an economy in apparatus,conductors and the like is effected and a flexible system is providedthat is capable of being suited to differing conditions in the areaaffected by the signals and is subject to control from a centralstation.

the traflic control system here described is derived from a variablespeed, constant voltage A. C. generator 10 which feeds to the two-wireline 11, 12. In this line, at the central station with the generator,are the rheostat 13 for varying line voltage, the disconnector switch14, which may be manual or automatic, and the indicator 15 which maycomprise a miniature of the system to show its operation and conditionat any instant.

At each street intersection is a set of lights L L each set being madeup of a group of lamps designed to flash red, amber or green, or certaincombinations of these colors. The lamps of the two sets are sointer-related that they give different color combinations forming signalunits. The group L faces traflic onthe main street and the group L facescross street traflic. The lamps may have lenses on opposite sides orthere may be two identical groups in each set, each two groups beingfaced oppositely on the street they control.

Two independent controls are provided for each set of lights L and LThere is a manual control M located at each intersection to control thesignals at that intersection individually and an automatic control, themechanism of which is mainly at the intersection, but this automaticmechanism is subject itself to control by the operator at the centralstation, such control being coincident at all stations in the system.

At each station, there are a. number of signal circuits leading to thelights L and L from a source of power which may be the line 11, 12 or itmay be separate as shown here at lines 18 and 19. When a separate sourceis availed of for the lights at each station, it may be either A. C. orD. C. regardless of which is used in the main power circuit. Thesefeeder circuits for the lights are selectively established and areprimarily governed from the central station by the dial B of switch Swhich determines the type of signaling which is in use at any one time,selecting from among constant one-color light, one-color light subjectto flash, and difierent color combinations alternating at regularintervals. The respective circuits thus selectively established by dial.8 are subject to secondary control, or government after establishment,by relay switches S S and S The circuits energizing the relay coils ofswitches S and S are fed and controlled from the main circuit 11, 12 andthe relays operating the switches S and S are selectively established incircuit by the dial C of the switch 8. Thus, as each signal circuitmeans is established by the dial B to effect a predetermined type ofsignaling by the lamp sets L and L, the appropriate governing meanstherefor is connected to the main circuit by the 'dial C.

The switch S may be termed an alternator switch since, when itsoperating means is put in the circuit by the dial C, it governs thesignal circuits correspondingly established through the light sets L andL by the dial B, to give alternate red and green with intermediate amberat regular intervals. By varying the details of the switch S and of itscontrol means, the distributor D, various combinations of red, green andamber or of any of them may be effected. This alternator is operated byrelays successively energized by circuits under the control of the motordriven distributor D the circuits for which are established by the dialC of the switch S from the power lines 11, 12.

The power to operate the controls throughout The system will now bedescribed in greater detail.

The main power line, which preferably is a two-wire line 11, 12, extendsthe length of the highway and, at each intersection on the highway,lines 16, 17 lead from it to operate the local devices for governing thesignal circuits, which themselves are established either from a localsource or from the power lines 11, 12 as may be convenient.

The feeders 18, 19 for the light circuits are shown here as forconnection to a local source. Feeder 18 is connected to dial B of switchS this dial having four series of contact plugs arranged radially. Anarm 20 is turned on the dial B, in a manner to be described, to bridgesuccessively each of the four radial series of plugs designated aspositions B B, B and B of the arm. Feeder 18 leads to the inner plug ofeach of the plug series B, B and B", but as shown, not to that of B asthat is the off position. It may, however, be connected to the innerplug of B From the outer three plugs of series B and B the wires R, Aand G lead to the alternator S, where wires R and G branch. From these,the branches R and R lead to the red lamps of the sets L and Lrespectively and branches G and G lead to the L and L green lamps inlike manner. Wire A after passing through switch S branches at 21 andits branches A and A lead to the amber lamps of the sets L and L At thejuncture between these main light iee'ders and their branches, thealternator S interposes switches shown diagrammatically. These switchesare of known type in which each movement of the actuator element in onedirection produces a reversal of the switch arm position,

the opposite movement of the actuator being idle.-

Such a switch is known and, of itself, forms no part of this invention.The actuator, it is noted, moves back to rest position after eachoperating movement. It will be understood that the drawings in thisrespect are schematic and not a true depiction of the switch structurebut only of its function.

Of the component switches of the alternator S switches 22 and 23 controlthe G and G branches, switches 24 and 25 control the R and R. branchesand switch 26 is inserted in the A line. In the positions of the variousswitch arms shown, the G and G conductors are connected and also the Rand R The manner in which these switches are successively operated tocause the cycle of signal combinations to be displayed and to berepeated regularly as long as may be desired will be describedhereinafter.

The parallel lamp circuits are completed by the connection of all of thelamps to the feeder 19.

From the three outer plugs of the B series on dial B, wires 27. 28 and29 lead to a two position constant light switch S wires 27 and 29connecting to the plugs 27a and 29a respectively on one side of theswitch and wire 28 connecting to the plug 28a on the other side. Abridging contact 30 moves between the two switch positions bridging thecontacts 27a and 27b and 29a and 29b in one position and 28a and 28b inthe other. It does not connect the plugs 29a and 271) as it has aninsulating portion between its two conducting portions.

From the plug 27b a line Rlconnects with the line R and from the plug29b a line R leads to the line R the two plugs being thereby con- Thereis provided, in line A a flashing device general type as the switches Sand S 280 of known type for automatically making and breaking thecircuit through the line A in response to current flow therein. If aconstant amber light were desired, a shunt could be provided around theflasher 280.

The switch S is of the same type as that described as being used in theunits of the alternator 8*. Its actuation and control will be describedhereinafter. I

Associated with the lamp circuits at each 10- cal station is a tell-talepanel of lamps Z Z duplicates of the sets L and L but of miniature size.This panel is connected to a switch S having arms forming a portion ofeach line, R R A, G and G in such a way that upon shifting of S each ofthe component arms of the latter is moved to the dotted line positionshown, thus transferring the circuits established by the dial B throughthe R R A. G and (3: leads to a connection with the tell-tale leads 1 ,1a, g and g and with the lamps Z 1 instead of with lamps L and L Switch Sis actuated by a solenoid 36 and is of the same Upon each energizationof solenoid 36 the arms are shifted from one position to the other.

This transfer of the light circuits to the miniature lamps is effectedby moving the switch arm 31 of the manual controller M to cover theplugs 32 and 33 on the panel of the controller thus closing acircuitfrom the feeder 18, through the 'wires 34, 35, the solenoid 36 and thewire 37 connected to feeder 19, causing the energization of the solenoid36 and a movement of the actua tor arm to shift the arms of the switch SThe panel of lamps l 1 should be mounted in a position in which they arereadily visible to the person operating the hand lever 31 by which thelocal station may be controlled independently of other local stationswhile the automatic control is transferred to the miniature lamp set.

Wires are also provided to feed the lamps L and L and to give a manualcontrol of the when the automatically governed lamp circuits aretransferred to the tell-tale lamps Z l'-. These wires lead to the panelwhich carries the plugs 32, 33 and on which also are four sets of con-.tact plugs 40, 41, 42 and 43 each having a plug connected by a bus 44and to the feeder 34 which leads from the main light feeder 13. Thewires 401, 402 form a circuit from the bus 44 through the plugs 40 andthrough the green L lamp and the red L lamp to feeder 19. In likemanner, the wires 421 and 422 connect the red L lamp and the green Llamp through the plugs 42. Wire 411 connects both amber lamps throughthe plugs 41, and the wires 431 and 432 connect both red lamps to theplugs 43, the latter connection thus duplicating the effect of the wiresR and R in the automatic control.

It will be apparent that upon swinging the arm 31, the first operationis to shift the switch S by bridging the contacts 32, 33. Theautomatically controlled circuits are thereby transferred to thetell-tale panel and the main lamps are left subject only to manualcontrol. Further movement of the arm 31 bridges in turn the plugs 40,

41 and 42 completing the several circuits described just above andgiving green, amber and red in succession on the main highway and red,amber and green respectively on the cross street. The operator can seefrom the tell-tale panel the condition of the automatic system and cansuit local signals thereto.

For clearing the intersection for fire apparatus, the arm 31 is putfully over to the right bridging the plugs 43 and establishing a circuitthrough both of the red lamps.

To put the system back under automatic control, the operator has simplyto swing the arm 31 fully back, the bridging of 32, 33 on the way givingan impulse to the relay 36 which will cause it to shift the switch S andto put its switch arms back in the position shown in full lines. Bywatching the tell-tale panel, the operator can put the local stationback in proper synchronism with the whole system.

Assuming the arm on the dial B of switch S to be in either the B or theB position establishing the R, A, G circuit for normal trafficconditions, the operation of the alternator S will occur as now will bedescribed.

The alternator, as stated above, comprises several switches having relayactuators 50, 51, 52 which shift the switch arms when the actuators aremoved in a single direction. The actuators are three in number, one 50for the switches 22 and 24, one 51 for the switch 26, and the third 52for the switches 23 and 25. It is to be noted that the switches 22 and24 have two on positions, while the switches 23, and 26 have an on andan off position. The effect of this upon the signal light sequence willappear hereinafter.

The relays are in circuits connected to the main power feeders 16, 17and established by the upper dial C 'of the switch S These circuitsinclude also the motor driven distributor D designed to causeenergization of the three relays in predetermined succession.

The distributor D comprises a fixed ring 53 having concentric circularslots in which contact plugs are adjustably secured. In the outer slotare two mutually insulated plugs 54, 55, and in the inner slot, twoother insulated plugs 56, 5'7.

In like manner, in slots in a movable ratchet toothed ring 58surrounding ring 53, there are my four insulated plugs, those designated59 and 60 being mutually insulated in the iimer slot and thosedesignated 61 and 62 being in an outer slot.

Referring to Figure 4, an arm 63 carrying a contact piece to engagethese plugs in passing is rotated by the electric motor 64 through theslip clutch and reduction gearing 65. The contact arm is secured to itsdrive shaft by a connection permitting relative movement between the twoif the arm is arrested but affording suflicient friction so that whennot positively arrested the arm will be rotated. The arm is electricallyconnected to one side (11) of the power circuit by'the wire 81 and inbridging the several contact plugs successively completes circuits inwhich are the relays 50, 51, 52. The latter are connected to the side ofthe power line (12) of opposite polarity by the wire 82.

The contact plugs 55 and 62 are connected with the relay 52, plugs 54and 61 with relay 50, and

the four plugs 56, 5'7, 59 and 60 are connected with relay 51 in themanner shown.

As the arm 63, rotating clockwise, passes over the plugs, circuits aresuccessively completed through the several relays causing movement ofthe switch actuator elements at predetermined intervals. As an example,arm 63 is shown as having just engaged plugs 5'7 and 55 causing theenergization of relays 51 and 52 and the movement of the switch arms 23,25 and 26 to positions shown.

This interrupts the circuit of the amber lamps of the sets L and L andcloses the lines G and R It may be assumed that at this time theswitches 22 and 24 are in the positions shown putting the lines G and Rin circuit giving a red light on the main street and a green light onthe cross street.

When the arm 63 has turned further it engages the plugs 60 and 62 andcompletes the circuits by which the relays 51 and 52 are againenergized, this time to open the switches 23 and 25 and to close theswitch 26. This causes amber to show on both streets, interrupts thecircuits causing red and green to show and gives warning that traffic isto change.

Shortly thereafter, the arm 63 reaches the plugs 59 and 61 and energizesthe solenoids 50 and 51, causing the shifting of switches 22, 24 and 26,to cut out the amber circuits because switch 26 is put in open positionand to bring the G and R lines into connection with the main G and Rlines through the switches 22 and 24 respectively.

When the arm 63 passes the plugs 54 and 56, the relays 50 and 51 areenergized to shift the switches 22, 24 and 26. By this, the lines G andR. are cut out by the change of position of the switches 22 and 24 andthe A circuit is closed by the closing of the switch 26.

Then, when the arm 63 bridges the plugs 55 and 57, the switch 26 isopened and the switches 23 and 25 are put in position to encircuit thelines G and R as described above.

It will be seen that this cycle as described involves a period of redlight on the main street with green on the cross street, followed by aperiod of amber light alone on both, and following that, a period ofgreen light on the main street with red on the cross street. In thesucceeding period, there is amber light alone on both streets justpreceding the change to red on the main street with green on the crossstreet.

At this point, it will be observed that the arrangement of circuits fromthe panel of the manual control M is'such that as the arm 31 is movedfrom left to right, a cycle of signals is given corresponding to thatcaused by one rotation of the arm 63 from its position bridging contactplugs 59 and 61. I

The above cycle of changes may continue to be repeated as long astrailic conditions warrant. At certain times, it is desirable to give alonger period of permitted traflic movement on one street than on theother. The present system provides for this by a ratio changer forvarying the relative duration of the red and the green light. Thevariation is effected by changing the angular spacing of the plugs inthe distributor D.

The outer ratchet toothed ring 58 carrying the contact plugs 59, 60, 61and 62, which determine the ending of the period of green light on themain street, is rotatable with respect to the inner ring 53 to vary theangular spacing between the said plugs and the other plugs on the ring53. To effect the rotation, the ring 58 has its outer edge toothed, asat 66, and with it is associated a pawl 67, driven by a relay actuatorrod 68 in one direction and by a spring 69, in the other. The relay isin a shunt between the feed line 17 and the wire 81 which leads throughthe dial C to feed line 16 and is adapted to be operated by a momentarydrop in voltage in the main circuit 11, 12.

The distributor D is provided with an interrupter dog '70 normally heldradially outward by a relay but it is adapted to be moved inwardly intothe path of the arm 63 by a spring whenever a drop occurs in the voltageof the current in the relay. Since the arm 63 is connected to the driveshaft by a slip connection, when the dog arrests the arm the drive shaftcontinues to turn.

Each arrester unit comprising a dog '70 and a relay '71 is adjustablymounted on an annular member outside the ring 58 so that by having thedogs on the several local units along the highway at predeterminedpositions with respect to their respective contact plugs, the wholesystem may be synchronized by arresting all the arms and then releasingthem simultaneously. On the other hand, if the angular spacing betweenthe arrester dog and the contact plugs isvaried progressively fromstation to station, then when all of the arms are releasedsimultaneously, the arms start in difierent parts of the cycle. Rotatingat uniform speed the arms maintain this difference and cause the cyclesof signals at the several stations to differ in phase. The system thusmay be made to give progressive signals of the wave type, so-called, nowin vogue.

The circuits through the distributor D and the relays 50, 51 and 52 areestablished by the upper dial C of the switch S This dial has fourradial series of contact plugs giving four positions for the movablecontact arm '75.

In position C the arm '75 bridges two plugs and forms a circuit from thepower line 16 through the wire and the relay operated arrester '71 tothe power line 1'7, thus bringing the arrester under control and holdingit outward, free of the arm 63. In this 0 position, no power is suppliedto any other part of the local system except to the motor 64 thru lines84, 86 which are independent of the dial C.

After having shut off the power in wires 11, 12, as may occur duringnight hours, for repairs or for any other reason, the switch 14 can beopened,

generator 10 brought into full operation, resisto tained in wires 11, 12by the rheostat 13 will not actuate the relays '71 at the severalstations to move the arrester dogs outward though the motors 64 areoperating normally. Operation of the rheostat 13 so as to cut out theresistance and raise the voltage in wires 11, 12 will thensimultaneously operate the relays '71 in all the local systems so thatthe distributor arms 63 will start to operate simultaneously in properphase relation. In this first position, however, no signals are givenbecause C on dial C corresponds to B on dial B. It is merely apreparatory stage.

In position C three plugs are bridged and a circuit is established fromthe line 16 through the wire 81 and thence to the centre of thedistributor arm 63. Depending on the position of the arm 63, the currentpasses through some or others of the plugs on rings 53 and 58 or it isinterrupted while the arm 63 is moving between plugs. When closed,however, by engagement of the arm and the plugs, the circuit includes,one, two or all, as the case may be, of the solenoids 50, 51,52 and iscompleted to the power line 1'7 by the wire 82.

The C position also establishes a circuit from line 16 through theinnermost plug on the dial C, through the line and the arrester relay 71to the line 17 thus keeping the arrester under control. With normalcurrent and voltage, the relay 71 holds the arrester dog outward, butupon drop of voltage, the dog is urged inward by its spring to arrestthe arm 63 at the predetermined point in the signal cycle.

In a shunt 83 from the line 81 to the power line 17, is the low voltagerelay 68 for the ratio changer.

The motor 64 is in a circuit not controlled by the dial C but consistingof a wire 84 from the line 17 through a wire to the motor windings andthence through a resistance 85, a hand switch S and the wire 86connected to the line 11. Thus, the motor 64 at each station isenergized whenever the generator 10 is operating, unless .the switch Sis opened to cut out the motor at that particular local station. Theresistance is variable to maintainuniform voltage across all of themotors in the system by compensating at the stations near the source ofpower for the drop in impressed voltage through the system.

In the C position of arm 75, the circuit through thedistributor isestablished as in the C position and, in addition, a circuit isestablished from the line 16 through the wire 87, the highway crossingswitch 88, and the wire 89 to the relay of a second arrester 711 and tothe power line 17.

The highway crossing switch.86 in the circuit is placed in thecross-street in a position to be operated by a passing autoist byreaching from his car or in any other suitable manner. This switch isheld closed by a spring, and so returns to closed position automaticallyafter being opened by a passing autoist.

Upon opening of the circuit by opening the switch 88, the dog of thearrester unit 711 is momentarily withdrawn by the spring and the arm 63is released to be turned one revolution giving one cycle of lights. Theswitch 88 is closed again in the meantime by its spring, thus givingeffect again to the current through the relay 711 which causes the dogto be inserted again in the path of the distributor arm. Thus thered'signal is given on the main street and the green on the crossstreet, giving the person a chance to cross the main street in safety.The relay 711 is to be so located with respect to the contact plugs thatexcept when someone so operates switch 88, the system is static withgreen showing on the main street and red on the cross street.

In the C position of the arm 75 on the dial C, a circuit is establishedfrom the line 16 through the wire 90 and the relay 91 of the low-voltagerelay switch S and thence to the line 17, thus bringing the switch Sunder control from the central station. Normally, when in the 0*position, the switch S will be in the dotted position, giving red lightson both streets. It a flashing light is desired, the central stationoperator merely throws resistance into the power lines 11, 12 by meansof the rheostat 13 and the low-voltage relay 91 moves the arm 30 to theposition bridging the plugs 28a, 28b. A second drop in voltage createdby operation of the rheostat will actuate the relay to return thebridging contact to the position in which it bridges the plugs 27a, 27band 29a, 29b.

The two dials B and C are actuated in synchronism so that their fourpositions correspond each to each as numbered, B to C etc. The comrelayswitches described, consisting of an arm 92 adapted to 'move the contactarms 20 and 75 from one position to another upon each impulse given tothe solenoid 93 of a no-voltage relay. The non-driving return movementof rod 92 is effected by a spring 94. If desired both movements may beretarded by a dash pot 95 so that a low voltage delayed action relay maybe used without being afiected by the operation of the quick actingrelays 68, 71, 711 and 91.

The following summary shows the eifect or the several positions of theswitch S upon both the control circuits established by the dial C andthe signal circuits established by the dial B. It will be recalled thatthe motors 64 at all of the stations are operating whenever the maincircuit 11, 12 is energized, assuming that the switch S at each stationis closed, and that the corresponding switches at all the stationsoperate simultaneously.

Position I B. No light circuits are established.

C. With the rheostat 13 causing reduced voltageand current, the dogs 70in the arrester units at the various stations are pressed downward bytheir springs as shown in Fig. 1 to arrest the distributor arms 63, andto bring all of the stations to the proper point for starting a seriesof signal cycles. When normal voltage is restored in the main circuitl1, 12, the arrester dogs are held outward and the distributor arms 63at the several stations are left free to rotate in the predeterminedphase relation. This C position may be maintained while the motors 64,if synchronous or single phase A. C. motors, may be brought to speed byknown mechanical means. In the 0 position of the dog of the relay 711 iswithdrawn so that it can not interrupt the operation of the distributorD.

' Position II B. The R, G, A, circuits are established for givingalternating signal combinations on both the main and the cross streetsin a regularly re peating cycle.

C. At each station, the arrester dog 70 is withdrawn. The ratio changeris in circuit so that it can be operated upon; momentary drop involtage. The circuit is established through the distributor arm 63 andthe relays 50, 51, 52 which operate the unit switches of the alternatorS The motor rotates the distributor arm 63 and causes the succession ofsignal combinations on the main and cross streets. This is the normalday time operating position and is the one for which the switches areshown set in the drawings.

Position III can open it and thereby momentarily allow the arrester dogto be withdrawn by a spring or other device and release the distributorarm for onerevolution giving one cycle of alternating lights at thatintersection.

out and the circuits 27, 28, 29 for one-color light,

red in both directions or flashing amber in both directions areestablished through the switch 8*. If the arm 30 of the switch S is inthe position indicated diagranmiatically in the solid lines, a flashingamber light is given due to the flasher 280. If the arm 30 is in theother position, a constant red light appears on each street.

C. All 'of the control circuits are cut out except the circuit throughthe relay 91 of the switch S Then upon operating rheostat 13 at thecentral station, the low-voltage relay 91 actuates the switch arm 30 inS to complete either the circuit through the red lamps or the onethrough the amber lamps.

For operation by direct current, little change is necessary. Figure 2shows those parts of the main current supply 11, 12 requiringmodification. At the central station, a variable speed direct currentgenerator is provided and with it a rheostat 101, a reversing switch102, an indicator 103 and a condenser 104.

A'direct current motor must be provided for each distributor D and withit a polarized relay to make certain that the current through the motorshall always be in one direction. Such a relay is shown in Fig. 3 as itwould be inserted in the system across the motor leads 84 and 86. Therelay includes two sets of leads 105, 106 and 107, 108 and two switches109, 110 having a common relay actuator 111 energized by the lead 84.Upon reversal of current, the switches 109, 110 are shifted. In oneposition they put the leads and 107 in circuit and in the other, theleads 106and 108, but in either case the direction of the currentthrough the motor 64 is the same.

The occasion for providing the polarized relay is to make it possible tooperate certain of the relays in the system by reversal of current aswell as by no- -voltage, low voltage and the like. These various ways ofselectively operating electrical devices in a large system are known perse and are included here under the phrase deflnition of devicesresponsive to a variation of the characteristics of the source of power.

An advantage of the A. C. system is in the possibility of usingsynchronous motors but these can not readily be started'and stopped. TheD. C. system, however, has the merit of requiring fewer turns in therelay windings, of giving a.

causes a change of motor speed. The "D; C. ap-

paratus must beso arranged that drop in voltage for the purpose oflowering the speed will not interfere with the selective operation ofthe low voltage relays. This may be done by having the relays operate ata lower voltage than the minimum used for speed variation, or preferablyby using no-voltage and reverse current relays.

The system, whether operated from a D. C. or

from an A. C. main circuit may be modified as shown on the third sheetof drawings. The several modifications there shown have in common thethought of operating the unit switches of the alternator switch S bymeans of two relays instead of three as in Figure 1, and further thereis shown in Figure 21 an arrangement by which the dials B and C of themain switch S are replaced by controllers madeup of groups of relayactuated switches. switch S may be used equally well with the alternatorS as shown in Figure l or with any one of the alternators shown inFigures 6, l1 and- 16.

In Figure 6, the dial B for selectively establishing the signal circuitsand the distributor D for controlling the alternator S are connected tothe other parts of the system in the manner shown in Figure 1. In the Bposition of the arm 20 no signal circuit is established. In the B and Bpositions, current is fed through the wire 115 to the signal lamps ofthe sets LE and L by way of the alternator S which here consists of fourswitch units of the type used in the Figure 1 arrangement. Two of theseswitch units, and 111, are simultaneously operated by the relay 50'while the other two 112 and 113 are simultaneously operated by the relay51'. It will be evident that the single wire 115 branched beforeconnection to the unit switches of the alternator S is equivalent to thethree wires R, A, G, in

Figure 1 leading from three plugs on dial B. So with the wire 114 incomparison with the wires 27, 28 and 29.

The relays 50 and 51' are alternately energized by the distributor D. Onthe distributor are four contact plugs, two of which, 116 and 117, areon the inner'ring 53 while two others, 118 and 119, are on the outerring 58 which is movable about the ring 53. As the arm 63 is rotated, acircuit is completed each time the arm 63 contacts with one of the fourplugs. Contacting with the plug 116, the arm 63 closes a circuit throughthe relay 50' and in like manner, upon contact with the plugs 118, 119,117, in succession, circuits are closed respectively through the relay51' then through the relay 50 and again through the relay 51'.

The alternate energization of the two relays causes the alternatereversal of the positions of the two groups of simultaneously operatedswitch units. With the circuits as shown in Figure 6,

this causes a cycle of signals known as the double amber and consistingfirst of green on the main street with red on the cross street, second,amber on both streets, then red on the main street with green on thecross street followed by amber on both streets. This cycle is repeatedas long as the distributor arm 63 continues to rotate with the arm 20 ofdial B in either the l?! or the B position.

It will be noted that the amber light shows only for a short intervalwhilethe arm 63 is travelling in one case from the contact plug 118 tothe plug 119 and in the other case from the plug 117 to the plug 116.The relay switch S operates in the same manner as in the Figure 1modification when the arm 20 of dial B is in its B position and isconnected to the lamps in the manner shown.

The cycle is the same as that of Figure 1.

Figures 7, 8, 9 and 10 represent diagrammatically the successivereversals of the positions of the switch arms during one cycle and thealternate operation caused by the alternate energization of the relays50' and 51'. Opposite each figure are two letters showing the color ofthe light appearing on the main street and on the cross streetrespectively when the switch units are in the relative positionsindicated in that figure. Figure 7 represents the position of theswitches shown in Figure 6. By reference to it, the circuits formed ineach of the succeeding switch positions represented by Figures 8, 9 and10 may be traced out with no difficulty.

In Figure 11 is shown an arrangement of switch units in the alternator Sby means of which a difierent type of signaling is effected. Thissequence is termed the single amber and consists first of a green lighton the mainstreet with a red on the cross street, second, an amber lighton the main street with the red continuing on the cross street, then ared on the main street with green on the cross street, followed by a redcontinuing on the main street, but with amber on the cross street. Thesuccessive positions of the switch units of the alternator shown inFigure 11 are schematically represented in Figures 12 to 15 inclusive.This arrangement involves the use of five switch units in the alternatorS three of these units being actuated by the relay 50 and two of them bythe relay 51'. The relays are alternately energized by circuitsestablished by the distributor D in the same manner as shown in Figure6.

In Figure 16 is shown still another modification to eiTect a diiferentsequence of signals. In this arrangement no amber light is used, thesequence consisting first of green on the main street with.

red on the cross street, then red on both streets followed by red on themain street with green on the cross street, and then again red on bothstreets. This arrangement likewise involves the use of five switch unitsin the alternator 5 the operation of the switch units being the same asin the arrangement shown in Figure 11. The whole difference is in thedifferent number of lamps used and in the different connection of thelamps to the switch units. It will be understood that the constant lightswitch S may be connected to the lamps in either of the arrangementsshown in Figure 11 and Figure 16.

Instead of using a rotary switch arm turnlng between two dials as shownin Figures 1 and 5, the main control switch S may be made up of relayswitches. In Figure 21 is shown an arrangement of switch units for thispurpose. A quick-acting low voltage relay switch 120 is connected acrossthe main circuit 11, 12; Associatedwith this switch are two delayedaction relays 121, 122 each operating a group of switch units of the twocontrollers C and B. These controllers correspond in function to thedials C and B shown in Figure 1. Simultaneous operation'of the twocontrollers is caused by the fact that certain switch units of each areoperated by the same relays 121 and 122.

The successive establishment of different control circuits by thecontroller C and of the different signal circuits by the controller B iseffected by the alternate energization of the two relays 121 and 122.The two relays are in circuit from the main feeder 12 through oppositesides of the relay switch 120 to the feeder 11 and are thus broughtunder control from the central station, being operable upon reduction ofvoltage in the main circuit.

Due to the fact that the relay 120 is quick-acting while the relays 121and 122 are slow-acting, a reduction in voltage in the main circuitcauses the relay 120 to operate before the relay 121 or the relay 122.Each energiaation of the switch relay 120 causes a. reversal of theposition of its switch arm and, depending upon the position to which theswitch arm is thrown thereby, either the relay 121 or the relay 122 isenergized. In this manner the relays 121 and 122 are alternatelyenergized by successive reductions of voltage in the main circuit tocause alternate operation of the two groups of switch units in thecontrollers C and B In Figure 22 are schematically shown the four aeffective to return the switch units from the C position to the Cposition.

In the C position a circuit is established from the feeder 16 to thewire and thence to the interrupter '71 as in Figure 1. In the C positioncircuits are established from the feeder 16 to the wires 80 and 81 and,the other parts of the systern being connected in the same manner as inFigure 1, the same result will be effected as by the 0 position of thearm 75 in Figure 1. So also with the C position in which the wire 8'? isconnected to the feeder 16, and with the C position in which the wire isconnected to the feeder 16 to encircuit the relay 91 of the constantlight switch S The position of the switch units of the controller B havenot been represented as they are readily understood. The position shownin Figure 21 is the B or off position. The actuation of relay 122connects the wire with the feeder 18. The actuation thereafter of therelay 121 does not change this but still does not encircuit the wire114. Upon the following actuation of the relay 122, however, to give the3* position, the wire 115 is disconnected and the wire 114 leading tothe signal lamps through the switch S is connected to the feeder 18.

The whole system has not been set out in showing the modification of thealternator and of the main control switch but the connection of themodified formsto the rest of the system has been indicated by giving tothe connecting wires the reference characters of the corresponding wiresin Figure l.

It will be clear from the foregoing that many variations of thecomponent parts of the system are possible, many of them beinginventions in themselves although still utilizing the underlying thoughtof the system. For instance, the arrangement of plugs on the distributorD and the connections to the alternator switch units may be varied togive difierent signal cycles. Other than motor operated distributors maybe used and I wish to include within the broader claims these otherdistributing means.

I claim 1. In a signaling system, a series of signal stationsseachprovided with visual signal means, a control station, a single maincircuit for controlling the system, said circuit connecting said signalstations to the control station,,means at each signal station to give aflashing signal, means at each signal station to give a'constant signal,means at each station operable by trafilc to cause said signal means togive routine control of traffic for a predetermined time, and meansoperable from the control station through said main circuit fordetermining which of the foregoing means shall be operative.

2. In a signaling system, a series of signal stations each provided withvisual signal means, a control station, a single main circuit forcontrolling the system, said circuit connecting said signal stations tothe control stations, means for giving a sequence of signals for theroutine control of traffic, means at each station operable by trafiic tocause said signal means to give routine control of trafiic for apredetermined time, and means operable from the control station throughsaid main circuit to determine which of the aforesaid means shall beoperative.

3. In a signaling system, a series of signal stations each provided witha plurality of visual signaling means, a control station, a single maincircuit for controlling the system, said circuit connecting said signalstations to said control station, means at each signal station to giveautomatically a predetermined sequence of signals of predetermineddurations for the routine control of trafilc, means at each signalstation for giving more than two variations of the ratio of durations ofsignals in the sequence, and means at the control station for actuatingsaid last mentioned means through said main circuit.

4. In a signaling system, a series of signal stations, each providedwith a plurality of visual signaling means, a control station, a singlemain circuit for controlling the system, said circuit connecting saidsignal stations with said control station, a plurality of means at thesignal station to cause a display of a plurality of types of signalingfor regulating traflic of different sorts such as routine traiiic, lighttraflic, or emergency traflic, means at the signal stations forselecting the type of signaling it is desired to display, means at thecontrol station for operating said selecting means through the maincircuit, and means at the signal station operable from the controlstation through said main circuit when said selecting means has selecteda certain type of signaling to change to a certain other type.

5. In a signaling system, a series of signal stations, each providedwith a plurality ofvisual signaling means, a control station, a singlemain circuit for controlling the system, said circuit connecting saidsignal stations with said control station, a plurality of means at thesignal station to cause a display of a plurality of types of signaling,said last named means including means giving a cyclical display for theroutine control of traflic, means to continuously display a desired oneof said signaling means, and means to continuously flash a desired oneof said signaling means, in combination with means at the signalingstations for selecting the type of signal it is desired to display,means at the control station for operating said selecting means throughthe main circuit and means at the signal station operable from thecontrol station through said main circuit, when said said selectingmeans has selected a certain type of signaling to change to a certainother type.

6. In a signaling system, a series or signal stations, each providedwith a plurality of visual signaling means, a control station, a singlemain circuit including a source of power for controlling the system,said circuit connecting said signal stations to the control station,means at each signal station to give a plurality of types of signalingcomprising means to give an intermittent signal, means to give aconstantly displayed signal, and means to give a sequence of differentsignals for the routine control of trafilc, in combination with means atthe signal station responsive to variation of the characteristics of thesource of power for determining which of said types of signaling, shallbe operative, said variation being transmitted through said main circuitfrom said control station.

7. In a signaling system, a series of signal stations, each providedwith a plurality of visual signaling means, a control station, a singlemain circuit including a source of power for controlling the system,said circuit connecting said signal stations to said control station,means at each signal station to give automatically a predeterminedsequence of signals of predetermined durations for the routine controlof traffic, means responsive to a change in the characteristics of thesource of power for giving more than two variations of the ratio ofdurations of signals in the sequence, said change in characteristicsbeing transmitted through said main circuit from said control station. a

8. In a signaling system, a series of signal stations, each providedwith a plurality of visual signaling means, a control station, a singlemain circuit including a source of power for controlling the system,said circuit connecting said signal stations to said control station,means at each station to give a plurality of types of signaling, one ofsaid types being a sequential display of signals of predetermineddurations for routine control of traiiic, means operable from thecentral station over said main circuit and responsive to a change incharacteristics of the source 01' power for selecting the type ofsignaling, a plurality of independent means for controlling the signalsor the given types of signaling, and means at the signal stationoperable upon a different change in the characteristics of the source ofpower for varying the ratio of durations in said sequential display,said changes in characteristics being transmitted through said maincircuit from said control station.

9. In a signaling system, a series of signal stations, each providedwith a plurality oi! visual signaling means, a control station, a singlemain circuit including a source of power for controlling the system,said circuit connecting said signal stations to said control station,means at each ferent change in the characteristics of the source circuitincluding a source of power for controlling the system, said circuitconnecting said signal stations to said control station, means at eachstation to give a plurality of types of signaling comprising means togive an intermittent signal,

means to give a constantly displayed signal, and means to give asequence of signals of predetermined durations for the routine controlof traflic, in combination with means at each signal station responsiveto a change in characteristics of the source of power in said maincircuit to select the type of signaling, means at the control station tochange the characteristics of the source of power in said main circuitto change the type of signaling.

11. In a signaling system, a series of signal stations, each providedwith a plurality of visual signaling means, a control station, a singlemain circuit including a source of power for controlling the system,said circuit connecting said signal stations to said control station,means at each signal station to cause a sequential display of signals ofpredetermined durations for the routine control of traillc, said meansbeing rendered operative or inoperativeupon a change in thecharacteristics of the source of power, means responsive to a differentvariation in the characteristics of the source of power to vary theratio of the durations of signals in said display, said changes incharacteristics being transmitted through said main circuit from saidcontrol station.

12. In a signaling system, a series of signal stations, each providedwith a plurality of visual signaling means, a control station, a singlemain circuit including a source of power for controlling the system,said circuit connecting said signal stations to said control station, aplurality of means at each signal station to give a cyclical type ofsignaling for routine control of traflic or a constant type of signalingfor light traflic conditions, means at each signal station for selectingthe type of signaling to be displayed, said selecting means beingresponsive to a change in the characteristics of the source of powertransmitted through said single circuit, means operable by traflicpassing a signal station to render said periodic means operative for onecycle when and whilesaid selecting means is in position to give theconstant type of signaling, said trafiic operated means beinginoperative while said selecting means is in position for routinecontrol of 13. In a signaling system, a series of signal stations, eachprovided with a plurality of visual signaling means, a control station,a single main circuit including a source of power for controlling thesystem, said circuit connecting said signal stations to said controlstation, a plurality of means at the signal station to give a pluralityoi. types of signaling for regulating traflic of different sorts such asroutine traflic, light trafllc or emergency traflic, means at eachsignal station for selecting the type of signaling it is desired todisplay, said selecting meansbeing responsive to a change in thecharacteristics of the source or power transmitted through said singlecircuit, means at the signal station responsive to a different change inthe characteristics of the source of power and operable from the controlstation through said single circuit to change a certain type of thesignaling to a certain other type when and while said selecting meanshas selected a certain other type,

14. In a signaling system, a series of signal stations, each providedwith a pluralityof visual signaling means, a control station, a singlemain circuit including a source of power for controlling the system,said circuit connecting said signal stations to said control station, aplurality of means at the signal stations to give a plurality of typesof signaling for regulating different sorts of traffic, one of saidtypes being a sequential display of signals of predetermined durationsfor the routine control of traffic, means for selecting the type ofsignaling it is desired to display, means to vary the ratio of durationsof signals given in said sequential display, said ratio-varying meansbeing responsive to a change in the characteristics of the source ofpower transmitted through said single circuit.

15. In a signaling system, a series ofsignal stations, each providedwith a plurality of visual signaling means, a control station, a singlemain circuit including a source of 'power for controlling the system,said circuit connecting said signal stations to said control station, aplurality of means at each.signal station to give a plurality of typesof signaling for regulating difierent sorts of traflic, one of said lastnamed means operating periodically. to give a sequence of signals ofpredetermined durations, means at each signal station operable from saidcontrol station over said main circuit for selecting the type ofsignaling, means for giving more than two variations of the ratio ofdurations of signals in the sequence, said ratio-varying means beingresponsive to a change in the characteristics of the source of powertransmitted through said single circuit.

16. In a signaling system, a series of signal stations each providedwith a plurality of visual signaling means, a control station, a singlemain circuit including a source of power for controlling the system,said circuit connecting said signal stations to said control station,plurality of means at each signal station for giving different types ofsignaling for regulating'diilerent sorts of traflic conditions, means ateach signal station for selecting the type of signaling, said pluralityof means including means at each signal station to give a sequence ofsignals of predetermined durations, means to render said sequentialmeans operative or inoperative upon a change in the characteristics ofthe source of power, and means to vary the ratio of the durations ofsignals in the sequence, said ratio-varying means being responsive to adifferent change in the characteristics of the source of power, saidchanges in characteristics being transmitted through said main circuitfrom said control station.

1'7. In a signaling system, a series of signal stations, each providedwith a plurality of visual signaling means, a control station, a singlemain circuit for controlling the system, said circuit connecting saidsignal stations to said control station, a plurality of means at thesignal station to give a plurality of types of signaling, including asequential display for routine control of trafiic and a type for lighttraffic, said type for light trafiic comprising means at each signalstation to permit traflic passing by a station to control the signalat-that station, means at each signal station to select the type ofsignaling it is desired to display, means at each station to stop saidsequential display at a predetermined point thereof, means at thecontrol station to determine which of the foregoing means shall beoperative, all of the aforesaid means being controlled from said controlstation through said single circuit.

ERNEST P. GOODRICH.

CERTlFICATE OF CORRECTION;

Patent No. 1,993,056. March 5, 1935.

ERNEST P. coomucu.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 3,second column; line 56, strike out the words "mutually insulated" andinsert the same after "being" in line 57; and page 8, first column, line60-61, claim 5, for "signaling read signal; and in same line 61, for"signal" read signaling; and that the said Letters Patent should be readwith these corrections therein that the same may conform to the recordof the case in the Patent Office.

Signed and sealed this 18th day of June, A. D. 1935.

Leslie Frazer (Seal) a 7 Acting Commissioner of Patents.

